U.S. patent application number 09/768492 was filed with the patent office on 2002-01-17 for polymers containing modified pigments and methods of preparing the same.
Invention is credited to Belmont, James A., Devonport, Wayne, Galloway, Collin P., Kutsovsky, Yakov E., Mahmud, Khaled, Mehos, Gregory J., Wang, Meng-Jiao.
Application Number | 20020006984 09/768492 |
Document ID | / |
Family ID | 22651837 |
Filed Date | 2002-01-17 |
United States Patent
Application |
20020006984 |
Kind Code |
A1 |
Mahmud, Khaled ; et
al. |
January 17, 2002 |
Polymers containing modified pigments and methods of preparing the
same
Abstract
A variety of methods to prepare a polymer composition containing
at least one polymer and at least one modified pigment are
described. The methods, in part, involve introducing a slurry
containing at least one modified pigment into an emulsion or
solution polymer prior to dewatering. Other polymer systems can be
used including aqueous based polymerizations and solvent-based
polymerizations, which can include free radical polymerizations.
Other methods involve the formation of a modified pigment in the
presence of an emulsion or solution polymer and then recovering the
polymer composition containing the modified pigment. Compositions
containing at least one modified pigment and the emulsion or
solution polymer are also described as well as uses for the polymer
compositions of the present invention.
Inventors: |
Mahmud, Khaled; (Natick,
MA) ; Belmont, James A.; (Acton, MA) ;
Kutsovsky, Yakov E.; (Arlington, MA) ; Devonport,
Wayne; (Tewksbury, MA) ; Wang, Meng-Jiao;
(Lexington, MA) ; Galloway, Collin P.; (Nashua,
NH) ; Mehos, Gregory J.; (Westford, MA) |
Correspondence
Address: |
Martha Ann Finnegan, Esq.
CABOT CORPORATION
157 Concord Road
Billerica
MA
01821
US
|
Family ID: |
22651837 |
Appl. No.: |
09/768492 |
Filed: |
January 24, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60178257 |
Jan 25, 2000 |
|
|
|
Current U.S.
Class: |
523/215 ;
524/495 |
Current CPC
Class: |
C08J 3/215 20130101 |
Class at
Publication: |
523/215 ;
524/495 |
International
Class: |
C08K 009/00; C08K
003/04 |
Claims
What is claimed is:
1. A method of preparing a polymer composition comprising at least
one polymer and at least one modified pigment, wherein said method
comprises introducing at least one slurry containing at least one
modified pigment to an aqueous-based polymer solution to form a
mixture; wherein said aqueous based polymer solution has not been
dewatered; and dewatering said mixture to form the polymer
composition.
2. The method of claim 1, wherein said aqueous-based polymer
solution is an emulsion polymer solution.
3. The method of claim 1, wherein said aqueous-based polymer
solution is a suspension polymer solution.
4. The method of claim 1, wherein said aqueous-based polymer
solution is a free radical polymer solution.
5. A method of preparing a polymer composition comprising at least
one polymer and at least one modified pigment comprising
introducing at least one slurry containing at least one modified
pigment to a precursor of an aqueous-based polymer solution;
conducting polymerization of the precursor to form a polymer
product; and dewatering the polymer product to form the polymer
composition.
6. A method of preparing a polymer composition comprising at least
one polymer and at least one modified pigment, comprising attaching
at least one organic group onto a pigment in the presence of an
aqueous-based polymer solution to form a polymer product;
dewatering the polymer product to form the polymer composition.
7. A method of preparing a polymer composition comprising at least
one polymer and at least one modified pigment, wherein said method
comprises introducing at least one slurry containing at least one
modified pigment to a quenched polymer solution and a
polymerization solvent to form a mixture; and washing said mixture
to form the polymer composition.
8. A method of forming a polymer composition comprising at least
one polymer and at least one modified pigment, wherein said method
comprises attaching at least one organic group onto a pigment in
the presence of a quenched and unwashed solution polymer and
polymerization solvent; and washing said mixture to form the
polymer composition.
9. A method of preparing a polymer composition comprising at least
one polymer and at least one modified pigment; wherein said method
comprises introducing a modified pigment having attached at least
one organic group into a solution containing at least one living
polymer; and terminating the polymerization of the living
polymer.
10. The method of claim 9, wherein said termination is accomplished
by at least one organic group attached and part of said modified
pigment.
11. A polymer composition comprising a slurry comprising at least
one modified pigment and a polymer solution.
12. The method of claim 1, wherein said slurry is produced by
micropulverizing modified pigment in water.
13. The method of claim 1, wherein said slurry is produced by
micropulverizing modified pigment in a solvent.
14. The method of claim 1, wherein said slurry is produced by
micropulverizing modified pigment in a dry process and then adding
ground pigment to a liquid in a separate mixer.
15. The method of claim 5, wherein said slurry is produced by
micropulverizing modified pigment in water.
16. The method of claim 5, wherein said slurry is produced by
micropulverizing modified pigment in a solvent.
17. The method of claim 5, wherein said slurry is produced by
micropulverizing modified pigment in a dry process and then adding
ground pigment to a liquid in a separate mixer.
18. The method of claim 7, wherein said slurry is produced by
micropulverizing modified pigment in water.
19. The method of claim 7, wherein said slurry is produced by
micropulverizing modified pigment in a solvent.
20. The method of claim 7, wherein said slurry is produced by
micropulverizing modified pigment in a dry process and then adding
ground pigment to a liquid in a separate mixer.
21. The method of claim 1, wherein said modified pigment is
modified carbon black, modified carbon fiber, modified activated
carbon, modified graphite, modified activated graphite, modified
carbon cloth, modified vitreous carbon, or combinations
thereof.
22. The method of claim 1, wherein said modified pigment is
modified carbon black.
23. The method of claim 1, wherein said modified pigment is
modified carbon product.
24. The method of claim 23, wherein said modified carbon product is
an aggregate comprising a carbon phase and a silicon-containing
species phase.
25. The method of claim 23, wherein said modified carbon product is
an aggregate comprising a carbon phase and a metal-containing
species phase or is a silica-coated carbon black.
26. The method of claim 23, wherein said modified carbon product is
a carbon product having attached aromatic sulfide groups.
27. The method of claim 1, wherein said modified pigment is carbon
black having attached at least one organic group.
28. The method of claim 27, wherein said organic group comprises an
aromatic group or a C.sub.1-C.sub.100 alkyl group, or both.
29. The method of claim 1, wherein said polymer is a solution SBR,
natural rubber, functionalized solution SBR, emulsion SBR,
polybutadiene, polyisoprene, or blends thereof.
Description
[0001] This application claims the benefit under 35 U.S.C. .sctn.
119(e) of prior U.S. Provisional Patent Application No. 60/178,257
filed Jan. 25, 2000, which is incorporated in its entirety by
reference herein.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to polymer compositions and
more particularly relates to polymer compositions containing
modified pigments and methods of making the same.
[0003] U.S. Pat. Nos. 5,559,169 and 5,851,280, incorporated in
their entirety by reference herein, describe polymer compositions
containing modified carbon products which are useful in a variety
of applications, such as plastics, tires, and other polymer
goods.
[0004] In making the polymer compositions containing the modified
carbon products or modified pigments, it would be beneficial if
improved methods could be devised to incorporate the modified
pigments into the polymer compositions. Typically, modified
pigments, such as modified carbon black, are formed in an aqueous
solution and this resulting slurry is dried, resulting in a dry
modified carbon black. This dry modified carbon black can then be
incorporated into polymer compositions and other compositions such
as inks and coatings. Thus, substantial cost is incurred in drying
the modified carbon black and in redispersing the product in the
polymer. Additionally, the modification process results generally
in the production of byproducts such as salts which are not readily
eliminated from the product.
[0005] The disclosed invention allows for a substantially improved
and more economical process. The separate drying step for the
carbon black may be eliminated. Additionally, the salt associated
with the product may be more readily eliminated. Furthermore, the
resulting elastomeric compound containing the carbon black and the
polymer will not require a separate redispersion step. Also, the
elastomeric compound will have a good carbon black dispersion and
therefore result in improved properties.
SUMMARY OF THE INVENTION
[0006] A feature of the present invention is to provide processes
for incorporating modified pigments into polymer compositions.
[0007] Another feature of the present invention is to provide
methods of introducing modified pigments into polymer compositions
which result in economical savings as well as reducing the amount
of time necessary to prepare polymer compositions containing
modified pigments.
[0008] Another feature of the present invention is to provide
products with superior dispersion of the components.
[0009] Another feature of the present invention is to provide
products with improved performance.
[0010] Another feature of the present invention is to provide
products substantially without the associated byproducts.
[0011] Additional features and advantages of the present invention
will be set forth in part in the description which follows, and in
part will be apparent from the description, or may be learned by
practice of the present invention. The objectives and other
advantages of the present invention will be realized and obtained
by means of the elements and combinations particularly pointed out
in the written description and appended claims.
[0012] To achieve these and other advantages, and in accordance
with the purposes of the present invention, as embodied and broadly
described herein, the present invention relates to a method of
preparing a polymer composition comprising at least one polymer and
at least one modified pigment. The method involves introducing at
least one slurry containing at least one modified pigment to a
polymer solution to form a mixture. The modification of the filler
is preferably done in an aqueous medium. At this stage, the polymer
solution has not been dewatered. After introducing the slurry, the
mixture is then dewatered to form the polymer composition. The
polymer solution can be a polymer emulsion, a polymer suspension,
or a polymer prepared by free radical polymerization. In addition,
polymers prepared by solvent based polymerizations can also benefit
from the methods of the present invention.
[0013] The present invention also relates to a method of preparing
the polymer composition by introducing at least one slurry
containing at least one modified pigment to a solution of the
precursor of an emulsion polymer. Polymerization of the precursor
is then initiated to form a polymer product. This product is then
dewatered to form the polymer composition of the present
invention.
[0014] In another method of preparing the polymer composition, the
method involves attaching at least one organic group onto a pigment
in the presence of a polymer emulsion to form a polymer product.
This product is then dewatered to form the polymer composition of
the present invention.
[0015] In addition, the present invention relates to a method of
forming a polymer composition by attaching at least one organic
group onto a pigment in the presence of a quenched and unwashed
solution of a polymer prepared by solution or suspension
polymerization and solvent. The mixture can then be washed and
dewatered to form the polymer composition of the present
invention.
[0016] In a further method of the present invention, a polymer
composition is formed by introducing at least one slurry containing
at least one modified carbon black or pigment to a quenched
solution of a polymer prepared by solution or suspension
polymerization to form a mixture. This mixture is then washed and
dewatered to form the polymer composition of the present
invention.
[0017] In a further method, the filler or pigment can be treated in
the aqueous phase of an emulsion or mixture of water and an organic
solvent. The modified filler or pigment is then transferred to the
organic solvent after treatment. This organic solvent solution can
be mixed with the solution of a polymer that is already formed or
with the polymer precursor solution. After formation of the
polymer, the resulting product can be washed and dewatered.
[0018] Finally, the present invention relates to a method of
preparing a polymer composition by introducing a modified pigment
having attached at least one organic group into a solution
containing at least one living polymer. The living polymer can then
be terminated by any technique including the option of at least one
organic group having a group capable of terminating the living
polymer and thus form a polymer composition of the present
invention.
[0019] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory only and are intended to provide further
explanation of the present invention, as claimed.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
[0020] The present invention relates to methods of preparing
polymer compositions containing modified pigments, wherein the
modified pigment has attached at least one organic group. The
present invention further relates to the resulting products from
these methods as well as the intermediate mixtures or compositions
formed during the methods of the present invention.
[0021] The modified pigment is a pigment having attached at least
one organic group. Examples of the pigment include, but are not
limited to, any colored pigment, carbon black, carbon fibers,
activated carbon, graphite, activated graphite, carbon cloth,
vitreous carbon, and the like. Preferably, the modified pigment is
a modified carbon product, such as modified carbon black. The
organic group which is attached onto the pigment can be any variety
of organic groups such as those described in U.S. Pat. Nos.
5,955,232; 5,922,118; 5,575,845; 5,630,868; 5,900,029; 5,895,522;
5,885,335; 5,851,280; 5,837,045; 5,803,959; 5,672,198; 5,571,311;
5,630,868; 5,707,432; 5,803,959; 5,554,739; 5,698,016; and
5,713,988; and PCT Publication Nos. WO 96/18688; WO 97/47697; WO
99/31175; WO 99/41304; WO 97/47692; and WO 97/47699; all
incorporated in their entireties by reference herein.
[0022] Also, for purposes of the present invention, a modified
carbon product includes an aggregate comprising a carbon phase and
a silicon-containing species phase. A description of this aggregate
as well as means of making this aggregate are described in PCT
Publication No. WO 96/37547 as well as U.S. Pat. Nos. 5,830,930;
6,008,272; 5,977,213; 5,948,835; 5,919,841; 5,904,762; 5,877,238;
and 5,869,550. This modified carbon product can be used as is or
can have an organic group attached thereto. All of these patents,
publications, and patent applications are hereby incorporated in
their entireties herein by reference.
[0023] The modified carbon product, for purposes of the present
invention, can also be an aggregate comprising a carbon phase and
metal-containing species phase where the metal-containing species
phase can be a variety of different metals such as magnesium,
calcium, titanium, vanadium, cobalt, nickel, zirconium, tin,
antimony, chromium, neodymium, lead, tellurium, barium, cesium,
iron, molybdenum, aluminum, and zinc, and mixtures thereof. The
aggregate comprising the carbon phase and a metal-containing
species phase is described in U.S. Pat. Nos. 6,017,480 and
6,150,453 and PCT Publication No. WO 98/42778 also hereby
incorporated in their entireties herein by reference. This carbon
product can be used as is or can have an organic group attached
thereto.
[0024] Also, for purposes of the present invention, a modified
carbon product includes a silica-coated carbon black, such as that
described in PCT Publication No. WO 96/37547, published Nov. 28,
1996, and U.S. Pat. No. 5,916,934 also hereby incorporated in their
entireties herein by reference. This modified carbon product can be
used as is or can have an organic group attached thereto.
[0025] Depending on the polymer composition, different organic
groups are preferred. For instance, if the polymer composition is
used in the formation of a tire or a component of a tire,
preferably, the organic groups are aromatic sulfides or thiols, or
the organic groups consist of amines, ionic groups, hydroxyl
groups, sulfur containing groups such as polysulfides, sulfenamide
groups, esters, ketones, or halogen containing groups. Another
group is phenylsulfatoethylsulfone which can be used to make a
charge stabilized dispersion of the filler or pigment in water and
then used later to provide improved filler polymer interaction once
in contact with the polymer.
[0026] Modified pigments, especially modified carbon products
having aromatic sulfide groups are particularly useful in elastomer
or rubber compositions. These aromatic sulfides can be represented
by the formulas Ar(CH.sub.2).sub.qS.sub.,(CH.sub.2).sub.1Ar' or
A--(CH.sub.2).sub.qS.sub.- K(CH.sub.2).sub.rAr" wherein Ar and Ar'
are independently substituted or unsubstituted arylene or
heteroarylene groups, Ar" is an aryl or heteroaryl group, k is 1 to
8 and q and r are 0-4. Substituted aryl groups would include
substituted alkylaryl groups. Arylene groups can include phenylene
groups, particularly p-phenylene groups, or benzothiazolylene
groups. Aryl groups can include phenyl, naphthyl and
benzothiazolyl. The number of sulfurs present, defined by k
preferably ranges from 2 to 4. Modified carbon products can have an
attached aromatic sulfide organic group of the formula
--(C.sub.6H.sub.4)--S.sub.k- --(C.sub.6H.sub.4)--, where k is an
integer from 1 to 8, and more preferably where k ranges from 2 to
4. Aromatic sulfide groups can be
bis-para-(C.sub.6H.sub.4)--S.sub.2--(C.sub.6H.sub.4)- and
para-(C.sub.6H.sub.4)--S.sub.2--(C.sub.6H.sub.5). The diazonium
salts of these aromatic sulfide groups may be conveniently prepared
from their corresponding primary amines,
H.sub.2N--Ar--S.sub.k--Ar'--NH.sub.2 or H.sub.2N--Ar--S.sub.k--Ar".
Groups include dithiodi-4,1-phenylene, tetrathiodi-4,1-phenylene,
phenyldithiophenylene, dithiodi-4,1-(3-chlorop- henylene),
--(4-C.sub.6H.sub.4)--S--S--(2-C.sub.7H.sub.4NS),
--(4-C.sub.6H.sub.4)--S--S--(4-C.sub.6H.sub.4)--OH,
6(2-C.sub.7H.sub.3NS)--SH,
--(4-C.sub.6H.sub.4)--CH.sub.2CH.sub.2--S--S---
CH.sub.2CH.sub.2--(4-C.sub.6H.sub.4)--,
--(4-C.sub.6H.sub.4)--CH.sub.2CH.s-
ub.2--S--S--S--CH.sub.2CH.sub.2--(4-C.sub.6H.sub.4)--,
--(2-C.sub.6H.sub.4)--S--S--(2-C.sub.6H.sub.4)--,
--(3-(C.sub.6H.sub.4)--- S--S--)3-C.sub.6H.sub.4)--,
-6-(C.sub.6H.sub.3N.sub.2S), -6-(2-C.sub.7H.sub.3NS)--S--NRR' where
RR' is --CH.sub.2CH.sub.2OCH.sub.2- CH.sub.2--,
-(4-C.sub.6H.sub.4)--S--S--S--S--(4-C.sub.6H.sub.4)--,
--(4-C.sub.6H.sub.4)--CH.dbd.CH.sub.2--(4-C.sub.6H.sub.4)--S--SO.sub.3H,
--(4-C.sub.6H.sub.4)--SO.sub.2NH--(4-C.sub.6H.sub.4)--S--S--(4-C.sub.6H.s-
ub.4)--NHSO.sub.2--(4-C.sub.6H.sub.4)--,
-6-(2-C.sub.7H.sub.3NS)--S--S-2-(- 6-C.sub.7H.sub.3NS)--,
--(4-C.sub.6H.sub.4)--S--CH.sub.2--(4-C.sub.6H.sub.- 4)--,
--(4-C.sub.6H.sub.4)--SO.sub.2--S--(4-C.sub.6H.sub.4)--,
--(4-C.sub.6H.sub.4)--CH.sub.2--S--CH.sub.2--(4-C.sub.6H.sub.4)--,
--(3-C.sub.6H.sub.4)--CH.sub.2--S--CH.sub.2--(3-C.sub.6H.sub.4)--,
--(4-C.sub.6H.sub.4)--CH.sub.2--S--S--CH.sub.2--(4-C.sub.6H.sub.4)--,
--(3-C.sub.6H.sub.4)--CH.sub.2S--S--CH.sub.2--(3-C.sub.6H.sub.4)--,
--(4-C.sub.6H.sub.4)--S--NRR' where RR' is
--CH.sub.2CH.sub.2OCH.sub.2CH.- sub.2--,
--(4-C.sub.6H.sub.4)--SO.sub.2NH--CH.sub.2CH.sub.2--S--S--CH.sub.-
2CH.sub.2--NHSO.sub.2--(4-C.sub.6H.sub.4)--,
--(4-C.sub.6H.sub.4)-2-(1,3-d- ithianyl;), and
--(4-C.sub.6H.sub.4)--S--(1,4-piperizinediyl)--S--(4-C.sub-
.6H.sub.4)--.
[0027] Another set of organic groups which may be attached to the
pigment are organic groups having an aminophenyl, such as
(C.sub.6H.sub.4)--NH.su- b.2,
(C.sub.6H.sub.4)--CH.sub.2--(C.sub.6H.sub.4)--NH.sub.2,,
(C.sub.6H.sub.4)--SO.sub.2--(C.sub.6H.sub.4)--NH.sub.2. Organic
groups also include aromatic sulfides, represented by the formulas
Ar--S.sub.n--Ar' or Ar--S.sub.n--Ar", wherein Ar and Ar' are
independently arylene groups, Ar" is an aryl and n is 1 to 8.
[0028] Preferably, the organic group comprises an aromatic group
and/or a C.sub.1--C.sub.100 alkyl group (and more preferably a
C.sub.1--C.sub.12 alkyl group) directly attached to the pigment,
with or without an ionic, ionizable, or polar group to improve
dispersion in aqueous media. For dispersions in organic solvents
such as toluene, the attached group is preferably non-polar or
non-ionic.
[0029] More than one type of organic group can be attached to the
pigment, or two or more types of modified pigments with different
attached organic groups can be used. Using two or more different
types of organic groups permits a combination of properties. If two
different types of organic groups are attached, for example, a
benzene sulfonic acid group and a vinyl aromatic group, the
sulfonic acid group promotes dispersibility and the vinyl aromatic
group serves as a radical grafting site. The ratio of the different
organic groups can be the same or different. Preferably, only the
minimum treatment level of the ionic, ionizable, or polar group is
used to impart stability to the dispersion. For example, groups
such as ionic species (e.g., sulphates, phosphates, alkali salts of
organic acids or quaternary ammonium salts), non-ionic species
(e.g., hydroxyl, organic acids) or surfactant stabilizers (e.g.,
SDMS, SDS, Antarox) can be used to provide stable pigment
dispersions in aqueous media. Dispersion of the modified pigment in
organic liquids can be facilitated in a similar manner by employing
treatments which are more compatible with these less polar
environments. Treatment levels of the organic group for purposes of
radical grafting sites can depend on material uses. For instance,
attachment of epoxy groups would facilitate grafting to hydroxyl
bearing polymer matrices such as polyurethanes or polycarbonates or
amine matrices such as nylon. Other examples include the attachment
of radical sensitive vinyl groups such as styrenics or acrylates,
to facilitate crosslinking type reactions in radical
polymerizations. These attached groups would ultimately affect the
properties of the materials containing these modified pigments. The
properties that would be affected include, but are not limited to,
impact behavior, modulus response, and dispersibility in
plastics.
[0030] Also, a combination of different modified pigments can be
used. For instance, a modified pigment having one type of organic
group attached thereto can be used in combination with another
modified pigment having a different organic group attached thereto.
Also, a modified pigment such as an aggregate comprising a carbon
phase and a silicon-containing species phase can be used in
combination with a modified carbon product having an attached
organic group, and so on.
[0031] At least one organic group can be attached onto a pigment by
a variety of mechanisms such as those described in the
above-described patents and publications. Preferably, the organic
group is attached chemically such as by covalent and/or ionic
bonds.
[0032] One process for attaching an organic group to the pigment
involves the reaction of at least one diazonium salt with a pigment
in the absence of an externally applied current sufficient to
reduce the diazonium salt. That is, the reaction between the
diazonium salt and the pigment proceeds without an external source
of electrons sufficient to reduce the diazonium salt. Mixtures of
different diazonium salts may be used in the process of the
invention. This process can be carried out under a variety of
reaction conditions and in any type of reaction medium, including
both protic and aprotic solvent systems or slurries.
[0033] In another process, at least one diazonium salt reacts with
a pigment in a protic reaction medium. Mixtures of different
diazonium salts may be used in this process of the invention. This
process can also be carried out under a variety of reaction
conditions. In both processes, the diazonium salt can be formed in
situ.
[0034] The processes can be carried out in any reaction medium
which allows the reaction between the diazonium salt and the
pigment to proceed. The reaction medium can be a solvent-based
system. The solvent may be a protic solvent, an aprotic solvent, or
a mixture of solvents. Protic solvents are solvents, like water or
methanol, containing a hydrogen attached to an oxygen or nitrogen
and thus are sufficiently acidic to form hydrogen bonds. Aprotic
solvents are solvents which do not contain an acidic hydrogen as
defined above. Aprotic solvents include, for example, solvents such
as hexanes, tetrahydrofuran (THF), acetonitrile, and benzonitrile.
For a discussion of protic and aprotic solvents see Morrison and
Boyd, Organic Chemistry, 5th Ed., pp. 228-231, (Allyn and Bacon,
Inc. 1987). The reaction between a diazonium salt and a carbon
product can take place with any type of carbon product, for
example, in fluffy or pelleted form.
[0035] The polymer in which at least one modified pigment is
combined with can be any polymer including natural products and
synthetic products. The polymer can be any type of polymer, such as
a random polymer, alternating polymer, graft polymer, block
polymer, star-like polymer, and/or comb-like polymer. The polymer
can also be one or more polyblends. The polymer can be an
interpenetrating polymer network (IPN); simultaneous
interpenetrating polymer network (SIN); or interpenetrating
elastomeric network (IEN). The polymer can be thermoplastic or
thermosettable.
[0036] Examples of polymers include, but are not limited to,
olefin-containing, diene-containing and butene-containing polymers
and copolymers. Particular examples include elastomers such as
solution SBR, natural rubber, emulsion SBR, polybutadiene,
polyisoprene, NBR, EPDM, EPM, isobutene elastomers, and their
functionalized or modified derivatives or blends thereof.
[0037] Other examples of polymers include, but are not limited to,
linear and non-linear polymers such as polyethylene,
poly(vinylchloride), polyisobutylene, polystyrene, polycaprolactam
(nylon), polyisoprene, and the like. Other general classes of
polymers include polyamides, polycarbonates, polyelectrolytes,
polyesters, polyethers, (polyhydroxy)benzenes, polyimides, polymers
containing sulfur (such as polysulfides, (polyphenylene) sulfide,
and polysulfones), polyolefins, polymethylbenzenes, polystyrene and
styrene copolymers (ABS included), acetal polymers, acrylic
polymers, acrylonitrile polymers and copolymers, polyolefins
containing halogen (such as polyvinyl chloride and polyvinylidene
chloride), fluoropolymers, ionomeric polymers, polymers containing
ketone group(s), liquid crystal polymers, polyamide-imides,
polymers containing olefinic double bond(s) (such as polybutadiene,
polydicyclopentadiene), polyolefin copolymers, polyphenylene
oxides, polyurethanes, thermoplastic elastomers, silicone polymers,
alkyd, epoxy, unsaturated polyester, vinyl ester, urea-, melamine-,
or phenol-formaldehyde resins, and the like. Preferably, the
polymer is an acrylic polymer, a methacrylic polymer, or a styrenic
polymer, but would largely depend upon the intended application.
For instance, reinforcement applications would generally involve
the formation of a rubber product that could be attached to the
modified carbon product in a manner such that the rubber product is
preferably not extractable, e.g., not extractable in solvents. This
can be accomplished by using a modified carbon product that has
styrenic groups attached to the surface. During an aqueous media
radical polymerization, the propagating chains could graft to these
sites on the surface of the modified carbon product and generate a
rubbery coated particle.
[0038] The polymers that are used in the methods of the present
invention are preferably formed from aqueous mediated
polymerization environments such as emulsion polymerizations and
suspension polymerizations and in general, free radical
polymerizations. Also, solvent based polymerizations can be used as
well. Accordingly, while emulsion polymerization and solution
polymerization are discussed in detail below, these methods can be
adapted to free radical polymerizations in general including, but
not limited to, suspension polymerizations and solvent based
polymerizations.
[0039] Many of the above-identified polymers can be prepared by
emulsion polymerization techniques and/or solution polymerization
techniques. For instance, styrene butadiene rubber can be prepared
by emulsion polymerization techniques. Those skilled in the art
will have a full appreciation for the various polymerization
techniques that can be used in the formation the above-described
polymers.
[0040] A variety of methods can be used to prepare a polymer
composition containing at least one polymer and at least one
modified pigment. Generally, the conventional ingredients used to
conduct the polymerization can be used in conventional amounts in
these methods, such as an initiator, surface active agents,
inhibiting or quenching agents, cross-linking agents, and the
like.
[0041] In one embodiment, the polymer composition containing at
least one polymer and at least one modified pigment is prepared by
introducing at least one slurry containing at least one modified
pigment to a polymer emulsion that has not been dewatered. The
introduction of the slurry to the polymer emulsion can be
considered a mixture for purposes of the present invention. This
mixture is then dewatered to form the polymer composition of the
present invention. Dewatering for purposes of the present invention
includes the removal of the aqueous or solvent phase, which may be
the continuous phase, to recover the formed polymer.
[0042] Conventional techniques can be used to accomplish the
dewatering of the mixture including decanting, filtering, and the
like.
[0043] In another method of the present invention, a polymer
composition can be formed by introducing at least one slurry
containing at least one modified pigment to a precursor of a
polymer emulsion. The precursor of the polymer emulsion is the
components which upon polymerization will result in a polymer
emulsion. Once the slurry is introduced into the precursor of the
polymer emulsion, the polymerization can be initiated to form a
polymer product. This polymer product can then be dewatered to
recover the polymer composition of the present invention.
[0044] Besides the above processes, the polymer composition can be
made by forming the modified pigment in the presence of the polymer
emulsion. In particular, the process involves attaching at least
one organic group onto a pigment in the presence of a polymer
emulsion to form a product. This product is then dewatered as
described above. In such a process, the reactants relating to the
formation of a modified pigment as described in the above-mentioned
patents and publications are used in the presence of a polymer
emulsion to conduct the reaction which will result in the
attachment of at least one organic group onto the pigment. Once
this reaction has been accomplished to form the modified pigment,
the modified pigment in the presence of the polymer emulsion is
subjected to a dewatering process to result in the polymer
composition of the present invention.
[0045] Generally, any salts or byproducts formed as a result of the
treatment of the filler or pigment are eliminated via the washing
and dewatering process of the polymer product.
[0046] In another embodiment of the present invention, a polymer
composition is formed by introducing at least one slurry containing
at least one modified pigment to a quenched solution of a polymer,
for instance, prepared by solution or suspension polymerization to
form a mixture. Essentially, in this process, a solution polymer
system is used wherein prior to washing the polymer solution, but
after quenching of the polymer solution, the slurry containing at
least one modified pigment is introduced. Once introduced, the
slurry present with the polymer solution which is quenched is then
washed using conventional techniques known to those skilled in the
art in recovering any polymer from a solution polymerization.
[0047] In yet another embodiment of the present invention, a
polymer composition is formed by attaching at least one organic
group onto a pigment in the presence of a quenched and unwashed
solution of a polymer, for instance, prepared by solution or
suspension polymerization and a solvent. Like one of the
embodiments mentioned above, in this embodiment, the modified
pigment is actually formed in the polymer solution and in the
presence of the components used in the solution polymerization. In
this case, the modification would occur in a two-phase mixture of
organic solvent and water. The treated pigment or filler is
transferred to the solvent phase. Thus, the reactants which are
used to form a modified pigment as described in the above-mentioned
patents and publications are introduced in the solution polymer and
the reaction initiated to form the modified pigment. Once the
modified pigment is formed in the presence of a quenched and
unwashed solution polymer, the solution polymer containing the
modified pigment is then washed using conventional techniques to
recover the polymer composition of the present invention.
[0048] Finally, in another embodiment of the present invention, a
polymer composition is formed wherein a modified dry pigment or
filler having attached at least one organic group is introduced
into a solution containing at least one living polymer. Preferably,
the modified pigment having attached at least one organic group has
a component on the organic group which is a terminating group
capable of terminating the polymerization. Examples of such groups
are esters, ketones, amines, and thiols.
[0049] The slurry containing modified pigment can be prepared in a
variety of ways. The slurry can be made by adding agglomerates of
carbon black or other pigment (pellets) to water. Preferably, the
pigment particles in the slurry are free of agglomerates so that
they will readily disperse in the polymer. One method of producing
an agglomerate-free modified pigment slurry is to make a paste
containing micropulverized solids. A device such as a ball mill is
used to micropulverize the pigment in the presence of a liquid such
as water or a solvent. Alternatively, a device such as a ball mill
can be used to deagglomerate the pigment without any liquid, and
then adding the micropulverized pigment downstream in a mixer.
[0050] The methods of the present invention can be incorporated
into the inventions described in WO 99/16600; WO 97/36724; and U.S.
Provisional Application No. 60/129,791; all incorporated in their
entireties by reference herein.
[0051] The intermediate products described above are considered
part of the present invention and are unique in the manner in which
the modified pigment is incorporated into the polymer. Thus, the
presence of the slurry containing the modified pigment in the
presence of the polymer solution in an aqueous based or solvent
based system are considered part of the present invention and
considered novel mixtures or compositions.
[0052] The polymer compositions of the present invention can be
used in a number of ways and in a number of applications including,
but not limited to, the following reinforcement applications,
rubber articles, plastic articles, and the like.
[0053] For instance, the modified pigment products of this
invention can be used as colorants in a plastic material. The
modified pigment products of the invention can also be used to
impart conductivity to a plastic material. The modified pigment
products of the invention may give an increased rate of dispersion
or improved quality of dispersion over the corresponding untreated
pigment. These improvements offer an economic advantage in plastic
manufacture and in value of the finished product, respectively.
Using the modified pigment products of the invention may improve
impact strength of the plastic. Thus, the invention relates to an
improved plastic composition comprising a plastic and the modified
pigment product.
[0054] As with conventional pigments, the modified pigment products
can be used with a variety of plastics, including but not limited
to, plastics made from thermoplastic resins, thermosetting resins,
or engineered materials, for example, composites. Typical kinds of
thermoplastic resins include: (1) acrylonitrile-butadiene-styrene
(ABS) resins; (2) acetals; (3) acrylics; (4) cellulosics; (5)
chlorinated polyethers; (6) fluorocarbons, such as
polytetrafluoroethylene (TFE), polychlorotrifluoroethylene (CTFE),
and fluorinated ethylene propylene (FEP); (7) nylons (polyamides);
(8) polycarbonates; (9) polyethylenes (including copolymers); (10)
polypropylenes (including copolymers); (11) polystyrenes; (12)
vinyls (polyvinyl chloride); (13) thermoplastic polyesters, such as
polyethylene terephthalate or polybutylene terephthalate; (14)
polyphenylene ether alloys; and blends and alloys of the above with
rubber modifiers. Typical thermosetting resins include: (1) alkyds;
(2) allylics; (3) the aminos (melamine and urea); (4) epoxies; (5)
phenolics; (6) polyesters; (7) silicones; and (8) urethanes.
[0055] According to the invention, the term plastic composition
includes, but is not limited to, any plastic material, article,
goods, surface, fabric, sheet, film, and the like. For example,
plastic materials include automotive parts, siding for homes,
liners for swimming pools, roofing materials, packaging materials,
synthetic fibers, food, and storage containers, light absorbing
applications (e.g., bar codes), and any variety of other household
or industrial items.
[0056] From the foregoing it will also be understood that the
present invention can be used in preparing polymer foams comprising
modified pigment. In preferred embodiments the filler is
preferentially located in the windows of the foam cells.
[0057] The modified pigment products of the present invention may
also be used, as with conventional pigments, in the compounding and
preparation of rubber and elastomer compositions. Accordingly, the
present invention relates to preparing a rubber or elastomeric
composition containing at least one rubber or elastomer and at
least one modified pigment using the methods of the present
invention.
[0058] Carbon blacks, for example, are useful in the preparation of
rubber vulcanizates such as those in tires. It is generally
desirable in the production of tires to utilize carbon blacks which
produce tires with satisfactory abrasion resistance and hysteresis
performance. The treadwear properties of a tire are related to
abrasion resistance. The greater the abrasion resistance, the
greater the number of miles the tire will last without wearing out.
The hysteresis of a rubber compound means the difference between
the energy applied to deform a rubber compound, and the energy
released as the rubber compound recovers to its initial undeformed
state. Tires with lower hysteresis values reduce rolling resistance
and therefore are able to reduce the fuel consumption of the
vehicle utilizing the tire. Thus, it is particularly desirable to
have carbon black products capable of imparting greater abrasion
resistance and lower hysteresis in tires.
[0059] The modified pigment products, and preferably the modified
carbon black products of this invention are useful in rubbers.
Carbon black products comprising an aromatic sulfides group are
preferred for this use. The carbon black products or other pigments
of the invention can be used in rubber compositions which are
sulfur-cured, peroxide-cured, or chemically crosslinked.
[0060] The modified pigment products of the invention may be used
with any of the polymers described above, including synthetic
rubbers such as: copolymers of from about 10 to about 70 percent by
weight of styrene and from about 90 to about 30 percent by weight
of butadiene such as copolymer of 19 parts styrene and 81 parts
butadiene, a copolymer of 30 parts styrene and 70 parts butadiene,
a copolymer of 43 parts styrene and 57 parts butadiene and a
copolymer of 50 parts styrene and 50 parts butadiene; polymers and
copolymers of conjugated dienes such as polybutadiene,
polyisoprene, polychloroprene, and the like, and copolymers of such
conjugated dienes with an ethylenic group-containing monomer
copolymerizable therewith such as styrene, methyl styrene,
chlorostyrene, acrylonitrile, 2-vinyl-pyridine, 5-methyl
2-vinylpyridine, 5-ethyl-2-vinylpyridine, 2-methyl-5-vinylpyridine,
alkyl-substituted acrylates, vinyl ketone, methyl isopropenyl
ketone, methyl vinyl either, alphamethylene carboxylic acids and
the esters and amides thereof such as acrylic acid and
dialkylacrylic acid amide; also suitable for use herein are
copolymers of dienes, ethylene, and other high alpha olefins such
as propylene, butene-1 and pentene-1. They can also be used with
natural rubber.
[0061] The rubber composition of the present invention can
therefore contain at least one elastomer, curing agents,
reinforcing filler, a coupling agent, and, optionally, various
processing aids, oil extenders, and antidegradents. In addition to
the examples mentioned above, the elastomer can be, but is not
limited to, polymers (e.g., homopolymers, copolymers, and
terpolymers) manufactured from 1,3 butadiene, styrene, isoprene,
isobutylene, 2,3-dimethyl-1,3 butadiene, acrylonitrile, ethylene,
propylene, and the like. It is preferred that these elastomers have
a glass transition point (Tg), as measured by DSC, between
-120.degree. C. and 0.degree. C. Examples of such elastomers
include poly(butadiene), poly(styrene-co-butadiene),
poly(isoprene), styrene-butadiene rubber (SBR), natural rubber, and
their oil-extended derivatives. Blends of any of the foregoing may
also be used.
[0062] Elastomeric compositions disclosed in the present invention
and which can be prepared include, but are not limited to,
vulcanized compositions (VR), thermoplastic vulcanizates (TPV),
thermoplastic elastomers (TPE) and thermoplastic polyolefins (TPO).
TPV, TPE, and TPO materials are further classified by their ability
to be extruded and molded several times without loss of performance
characteristics.
[0063] The elastomeric composition may include one or more curing
agents such as, for example, sulfur, sulfur donors, activators,
accelerators, peroxides, and other additive systems used to effect
vulcanization of the elastomer composition.
[0064] The resultant elastomeric compounds containing the modified
pigment, and preferably modified carbon black of the present
invention and optionally containing one or more coupling agents may
be used for various elastomeric products, including tires and
components thereof, such as a tread compound, undertread compound,
sidewall compound, wire skim compound, innerliner compound, bead,
apex, any compound used in carcass and other components for vehicle
tires, industrial rubber products, seals, timing belts, power
transmission belting, and other rubber goods.
[0065] Advantageously, the modified pigment products, and
especially the modified carbon black products of the present
invention can impart improved abrasion resistance and/or reduced
hysteresis to rubber or elastomeric compositions containing
them.
[0066] The modified pigment products of this invention may also be
used to color fibers or textiles. Preferred modified pigment
products for this use are the dispersible modified pigment
products. Accordingly, the invention relates to fiber and textile
compositions comprising a fiber or textile and a modified pigment
product. Fibers suitable for use comprise natural and synthetic
fibers such as cotton, wool, silk, linen, polyester and nylon.
Textiles suitable for use comprise natural and synthetic fibers
such as cotton, wool, silk, linen, polyester and nylon. Preferably
natural fibers and textiles comprising cotton, wool, silk, and
linen are used.
[0067] The modified pigment products of the present invention may
be colored by means known in the art to color fibers and textiles
with, for example, direct and acid dyes. Also, the modified
pigments can be incorporated into fibers by spinning techniques,
such as wet spinning, dry spinning, and melt spun techniques. For a
general discussion of coloring with dyes, see Kirk-Othmer
Encyclopedia of Chemical Technology, Vol. 8 pp 280-350 "Dyes,
Application and Evaluation" (John Wiles and Sons, 1979),
incorporated herein by reference. Use of a water or solvent
dispersible modified pigment product discussed above provides a
method for coloring these materials with a lightfast colorant.
[0068] The present invention also relates to toner compositions
comprising toner resin particles and the modified pigment particles
of the present invention wherein the toner resin particle can be
formed using the methods described herein. Conventional additives
as described in U.S. Pat. Nos. 5,278,018; 5,510,221; 5,275,900;
5,571,654; and 5,484,575; and EP O 270-066A1 can be used and these
patents are incorporated herein by reference.
[0069] Other embodiments of the present invention will be apparent
to those skilled in the art from consideration of the specification
and practice of the invention disclosed herein. It is intended that
the specification and examples be considered as exemplary only,
with a true scope and spirit of the invention being indicated by
the following claims and equivalents thereof.
* * * * *